However, in the past day the screen has started flickering, most of the time when the keyboard is open. It can do it when it's just sitting there, but it usually only happens when I pick it up, place stress on the case by hitting a button, or press the screen with any additional force than a nominal "touch" gesture.

Frequency is pretty quick, maybe around 20Hz or so. It doesn't flicker out completely, it seems to irregularly oscillate between 100% brightness and 20% brighntess.

Based on the fact that I can make it happen by opening the KB and pushing the screen, it is a hardware issue. I have tried tightening the battery with paper inserts which doesn't help. Any other ideas?